A common problem involved in the user of a plurality of extension cords connected end to end concerns the inadvertent uncoupling of plugs from sockets. When one cord is pulled and another is held by an obstruction, the plug and socket between those two cords are separated, terminating electrical power to the tool.
Conventional arrangements for securing the coupling between the plugs and sockets of connected electrical extension cords have not been particularly successful. Such arrangements do not provide a secure enough connection and/or are unacceptably complex and expensive to manufacture and operate. Additionally, these arrangements tend to be fairly limited in the types of plugs and sockets with which they can be used. Typical examples of these conventional systems for coupling electrical plug connectors are disclosed in U.S. Pat. No. 2,725,543 to Tanner; U.S. Pat. No. 3,475,716 to Laig; U.S. Pat. No. 4,097,105 to Zumwalt; and U.S. Pat. No. 4,514,026 to Herbert.